In the photolithography process which is one manufacturing process for micro devices such as semiconductor devices and the like, an exposure apparatus is used which exposes a pattern image of a mask onto a photosensitive substrate. This exposure apparatus has a mask stage for holding a mask and a substrate stage for holding a substrate, and exposes a pattern image of the mask on the substrate via a projection optical system. In the manufacture of a micro device, in order to increase the density of the device, it is necessary to make the pattern formed on the substrate fine. In order to address this necessity, even higher resolution of the exposure apparatus is desired. As one means for realizing this higher resolution, there is proposed a liquid immersion exposure apparatus as disclosed in the following Patent Document, in which a liquid is filled in an optical path space of the exposure light between a projection optical system and a substrate, and the substrate is exposed via the projection optical system and the liquid.
Patent Document: PCT International Publication No. WO 99/49504